Dual wheel mounting



May 9, 1950 c. s. ASH 2,507,134

DUAL WHEEL MOUNTING Filed June 2, 1948 2 Sheets-Sheet 1 INVENTOR CH/UPL ES 5. ASH

A ORNEYS May 9, 1950 c. s. ASH 2,507,134

DUAL WHEEL MOUNTING Filed June 2, 1948 2 Sheets-Sheet 2 y Y W was Patented May 9, 1950 UNITED STATES PATENT OFFICE DUAL WHEEL MOUNTING Charles S. Ash, Milford, Mich.

Application June 2, 1948, Serial No. 30,657

Claims.

The invention relates to new and useful im- I provements in dual wheel assemblies, and more particularly to such improvements in dual, driven. differential, dirigible wheel assemblies.

Objects and advantages of the invention will be set forth in part hereinafter and in part will be obvious herefrom, or may be learned by practice with the invention, the same being realized and attained by means of the instrumentalities and combinations pointed out in the appended claims.

The invention consists in the novel parts, constructions, arrangements, combinations, and improvements herein shown and described.

The accompanying drawings, referred to here in and constituting a part hereof, illustrate one embodiment of the invention, and together with the description, serve to explain the principles of the invention.

Of the drawings:

Figure l is a vertical sectional view of a dual, driven, differential, dirigible wheel assembly embodying the present invention;

Figure 2 is a cross-sectional view taken along the line 22 of Figure 1; and

Figure 3 is a detail plan view of certain of the differential means of the invention taken along line 3-3 of Figure 2.

It is an object of the present invention to provide an improved dual wheel assembly for automotive vehicles in which the two wheels of the assembly are capable of independent relative rotation in order to prevent the dragging of either wheel when the vehicle is travelling around a corner and the excessive and unnecessary tire wear incident to such dragging. A further object of the invention is the provision in such a Wheel assembly of improved bearing and lubricant retaining means. The invention is particularly applicable to driven independently rotatable dual wheel assemblies, and it is an object of the invention to provide therefore improved bearing and housing means for the gearing mechanism of the Wheel assemblies.

Referring now in detail to the embodiment of the invention shown by way of example in the accompanying drawings, and. referring particularly to Figure 1, the live axle shaft In of an automotive vehicle is mounted in the hollow axle housing II, it being understood that the members of the dual wheel assembly herein shown and described are duplicated at the opposite end of the axle housing I! on the other side of the vehicle. A spherical knuckle I2 is formed integral with housing I I at its end, and seated in recessed portions at the top and bottom of the knuckle are 2 bearings 13 in which are journalled the reduced end portion of king pins I 4. The outer thickenedportions of king pins [4 are seated in circular apertures in yoke arms I! and maintained therein by cap plates l8 which are firmly secured to the yoke arms.

The yoke arms I! at their outer ends carry by means of cap screws IS the hollow stub spindle 20, and a steering arm 2| is connected to the upper yoke arm in order to impart steering movement to spindle 20 by means of any conventional and suitable steering gear mechanism. Within the spindle 20 ispositioned the live stub shaft 22 to furnish power to the dual wheels of the assembly, said shaft receiving its power from the live axle it] through a suitable universal joint, which in Figure 1 is indicated by the numeral 23 and is shown as a Marmon-Herrington construction.

A cylindrical driving sleeve 25 of greater diameterthan the spindle 20 is positioned over the spindle and is rotatably -mounted thereon by means of tapered roller bearings 26 and 21. The inner bearing 26 is seated by its inner race against .a substantial shoulder 28 of the spindle 20,.and by its outer race against an inwardly extending annular shoulder 29 of the driving sleeve 25. The other or outer tapered roller bearing 21 has its outer race seated against a second inwardly extending annular shoulder 30 of the driving sleeve. A retaining nut 32 threaded on the end of spindle 2Q with an interposed washer 33 engages the'inner race of bearing 21 and holds the bearings and driving sleeve in place upon the spindle. A look nut 34 may also be threaded on the end of the spindle. The bearings 26 and 21 are thus firmly positioned for the function of anti-friction and anti-thrust between the spindle 29 and the driving sleeve 25. A driving connection is established between the live stub shaft 22 and the driving sleeve 25 by means of the member 36 which has an annular portion 3'! secured to the sleeve by means of bolts '38 and a cylindrical portion 39 which has inwardly projecting teeth to mesh with the end of-the stub shaft which is formed as a broad face pinion gear.

The outer wheel hub 40' is journalled on the outer end of driving sleeve 25 for relative rotation with respect thereto,-and-the outer wheel 4! is supported on the hub i8 and'secured for rotation therewith by means of pins JZWhlCh extend through a'fiange portion '43 of the hub and into a-suitable aperture in the wheel. The pins 42 are maintained in place by a cover plate 44 which extends over the end of the stub shaft and driving sleeve assembly, and is secured to flange 93 of the outer wheel hub 40 by a plurality of cap screws 45. The hub 40 abuts against the annular portion 3! of the member 36 which maintains the hub in place upon the driving sleeve and. acts as a thrust bearing between the members.

The inner wheel hub 55 is journalled on the inner end of driving sleeve 25 for relative rotation with respect thereto, and supports the deeply inwardlydishedinner wheel 5|. Thehub 53 has a flange portion 52 which abuts :againstanintegral outwardly extending flange portion 53 of the driving sleeve 25, whereby the hub is maintained in position and a thrust bearing effected. A plurality of pins 54 extending through 'Eflange 52 and into wheel 5| near its inner;- pe phery,

secures the wheel to its hub for rotation therewith. Each of the vehicle wheels '-:4l,'15j| ;is -.zpro-i vided with a suitable pneumatic tire supporting rim 55 and means of any convenient type for demountably mounting the tire rim on the wheel.

The differential "-driving means betweenthe betweenthe innerand outerwheel-hubsfor-rotation therewith. A plurality of circumferentially spaced -cap screws '6! pass through apertures provided in the spider ring and are securely "threaded into driving sleeve in the thickened central portion thereof providedgby the shoulder 30. Other longer :oap screws 52 are similarly positioned inthe spider ring =60 and driving sleeve '25 and have 'rotatably. mounted about the outer :portion of their length 'the helicalpinion-idler 4 the whole power to the ineffective wheel and result in the stalling of the vehicle.

The torque transmission from one wheel to the other through the helical ring gear teeth 6?, the

5 spiral pinion gears 65 and the helical pinion idler 10 -angle.A,.in Figure 3 of the accompanying drawings and is illustratively shown as Thus a smaller helix angle will result in a greater torque transmission to one of the wheels by turning the xother and a greater helix angle will result in a 15 .lesser. .torque transmission. The helix angle given to the spiral pinion gears 65 may be as high as=?"* and this construction results in the transmission of relatively little torque from one wheel to the other, or stated another way, re-

20 sults in a comparatively free differential action .between'the individual-wheels of the"dua'lwheel "assembly. The helix angle chosen may be a -smaller one, dependingupon'the "freedom ofthe differential action desired,'but the angle can'in .25110 case besma'ller than a critical angle beyond "which the work pinion gears become non-re- -versible. By non-reversible" is meant a condition where full torque is transmitted'to one "wheelby the turning of the other, and in this condition the wheels are as effectively locked againstthe desired differential action 'as though they'were bolted together,-as'-is the case-with non-independently rotatable dual wheel struc- "tures. :Such :an effect destroys completely the gears 63 of the differential means. 'Each":-such*"- gadvantages oftheindependentlyrotatabledual helical pinion idler .gear is in'mesh with a pair of worm pinion gears .65, which are positioned :on either side of the idler gearaxially of:the driving sleeve 25. .The worm.pinions: are rotatably mounted ,in transverse'hangers .Whichfjlle an integral partof spiderring '60. The ends'of'the inner and .outer wheelhubs dil and .50 adjacent .spider jring ,60 .are .formed .with helical teeth 61, as shown in ,Figure 3,. towfo rm. alhelical .worm

' wheel structure and is, therefore; to ice-avoided.

"The" helix angle '"for the worm-pinion gearslfi5 in accordance with the present invention is. therefore, greater than the-critical angle at which said worm pinionsbecome non-reversible, andit' has been;found that the angle should not be smaller than 20 in order to obtain a differential action between the wheels. Thus, a vhelix angle between the critical angle and an .gear as an. integr'al., part.of;each.hub,.and the an le of 45 may belchosen; d pen in up the :helicalteeth 61 are. in mesh with the worm pinion gears 65.

.bevel pinion gears .only -iarequtilized -;is in the. fact :that the former. is "more sluggishin its operation.

freedom with which it is desired .for the differential action to. occur, and varioushelix angles of less than 45 result in differential actionwhich is more or less limited.

Thrust'bearing and differential gear protection means are provided on the dual wheels 4| 7 and .5l andas illustratively embodied comprise a curved annular flange member Til formed integral with'the outer wheel 4 l .at its inner periphery and That the/Worm pmllonli'ypeidifierentml 565 a similar member'll of the inner wheel 5|. These VidQSimOIG resistance to tthe movement of one wheel by themovementoftheother:throughthe worm pinion gears.65 and-.theahelicalapinion idler gears 63, due to the .wedging.or;-sliding action in members 'Hl'and H extend toward each other 'and'encircle'the' worm piniongears 65, thehelical pinion idler'gears 63'and the other members of the differential. At their adjacent peripheries :themesh of ithejgears. .Such resistance is de- .thecflange members H have thickened sirable and necessary in :a wheel assembly such as that of the present invention, where itmay occur =onuneven .or slippery surfaces that one-of the wheels of the. assembly may have :suincient tions "l2 and Brespectively, on which are formed opposed paralled radial surfaces 12 and 13' respectively which; with an interposed bearing ring '74;-form-thrust bearings between the dual wheels traction with th a m While m hag-little and serve toproperly'sp'ace the worm pinion ears -or none.

' "When such conditions are encountered "with the assembly of -;the-p resent invention ample power may still be continuously transmitted to *65 and the helical-pinion idler gears 63. The portions 72, 13 further haveform'e'd thereon outward facing bearing surfaces 98 and 99 respectively which arein'clined with respect to the axis the-wheel with the better traction although some floor thewheels, a=45 angle of inclination being power-is lost'in the inefiective rotation :or slippins of the wheel without-traction. 'Themore conventional type-of differential, such as is shown ':in the prior patent to 'Rumpler, German No.

"illustrated and preferred.

' An annular ring 15 of V-cross section encircles the enlarged bearing portionslZ, '13 of the-wheels, and "is formed with grooves adjacent the flange 466,062, 'however,"-would transmit substantially members 10 and 1 l inwhich sealing rings 16 are 'p'ositioned'in order to prevent the loss'of lubricat- "ing material from thediiferential housingand seen in Figure 2, which are adjustably secured together by bolts 58' and nuts 19. By the engagement of the inclined faces I and ll of ring 15 with the cooperatingly inclined faces 98 and 99 of the enlarged bearing portions 12 and 13 an effective diametrally adjustable bearing is achieved adapted to resist the axial thrust of wheels 4| and 5! away from each other.

Braking means for the dual wheel assembly are provided connected to the driving sleeve 25 so that the retarding action may be transmitted to the individual wheels through the differential mechanism. Thus braking effort is exerted upon both wheels of the assembly, and the advantages which have been described for the differential of the present invention are utilized to the same extent in braking the vehicle as in driving it. As illustratively embodied these means comprise an inwardly dished annular brake drum supporting member 90 which is bolted to an outwardly radially extending radial flange 9! integral with hearing flange 53 of driving sleeve 25, whereby the supporting member 90 rotates with the driving sleeve. A brake drum 92 is carried by supporting member 913 for rotation therewith, and a brake band 93 is carried by brake anchor member 94 to be expanded by any suitable and conventional means against the inner surface of brake drum 92.

The invention in its broader aspects is not limited to the specific mechanisms shown and described but departures may be made therefrom within the scope of the accompanying claims without departing from the principles of the invention and without sacrificing its chief advantages.

What is claimed is:

1. In a differential dual wheel assembly, in combination, two coaxially supported independently rotatable wheels, said wheels comprising adjacent opposed flange portions, said portions having opposed radially extending bearing surfaces formed thereon, said portions further having outward facing bearing surfaces formed thereon and inclined with respect to the axis of said wheels, and a pair of semi-circular rings interconnected and diametrally adjustable and having inclined converging bearing surfaces adapted to engage said outward facing bearing surfaces.

2. In a differential dual wheel assembly, in combination, a pair of coaxially supported independently rotatable wheels having adjacent portions with opposed radially extending bearing surfaces and other bearing surfaces inclined with respect to the axis of said wheels, and a bearing ring having inclined converging surfaces to engage said other bearing surfaces, said radial and inclined surfaces providing bearings between the wheels for axially directed thrust in either direction.

3. In a diiferential dual wheel assembly, in combination, a pair of coaxially supported independently rotatable wheels, bearing means between said wheels comprising a pair of bearing members having opposed radially extending surfaces each said member secured with respect to a respective one of said wheels and another pair of bearing surfaces on said members, said other pair of surfaces being inclined with respect to the axis of said wheels, and a bearing ring having inclined converging surfaces to engage said other pair of bearing surfaces, said radial and inclined surfaces providing bearings between the wheels for axially 'directed thrust in either dire} tion. 5

4. In a diiferentlal dual Wheel assembly, in

combination, a pair of coaxially supported independently rotatable wheels, bearing means between saidwheels comprising a pair of bearing members having opposed radially extending surfaces each said member secured With respect to a respective one of said Wheels and anotherpair of bearing surfaces on said members, said other pair of surfaces being inclined with respect to the axis of said wheels, and a pair of semi-circular rings interconnected diametrally adjustable and having inclined converging bearing surfaces adapted to engage said other pair of bearing surfaces.

5. In a differential dual wheel assembly, in combination, a pair of coaxially supported independently rotatable wheels, bearing means between said wheels comprising a pair of bearing members having opposed radially extending surfaces each said member secured with respect to a respective one of said wheels and another pair of bearing surfaces on said members said other pair of surfaces being inclined with respect to the axis of said wheels, a bearing ring having inclined converging surfaces to engage said other pair of bearing surfaces, and sealing means between either edge of said bearing ring and said wheels.

6. In a differential dual wheel assembly, in combination, a pair of coaxially supported independently rotatable wheels, bearing means between said wheels comprising a pair of bearing members having opposed radialy extending sur-- faces each said member secured with respect to a respective one of said wheels and another pair of bearing surfaces on said members said other pair of surfaces being inclined with respect to the axis of said wheels, a bearing ring having inclined converging surfaces to engage said other pair of bearing surfaces, and sealing means between either edge of said bearing ring and said bearing means.

7. In a diiferential dual wheel assembly, in combination, a pair of coaxially supported independently rotatable wheels, means forming an enclosed annular chamber between said wheels comprising a pair of annular elements each secured with respect to one of said wheels and having opposed radially extending bearing surfaces and other bearing surfaces inclined with respect to the axis of the wheels, and a bearing ring having inclined converging surfaces to engage said other bearing surfaces.

8. In a differential dual wheel assembly, in combination, a pair of coaxially supported independently rotatable wheels, means forming an enclosed annular chamber between said wheels comprising a pair of annular elements each secured with respect to one of said Wheels and having opposed radially extending bearing surfaces and other bearing surfaces inclined with respect to the axis of the wheels, a bearing ring having inclined converging surfaces to engage said other bearing surfaces and sealing means between either edge of said bearing ring and respective ones of said elements.

9. In a differential dual wheel assembly, in combination, a pair of coaxially supported independently rotatable wheels, means forming an enclosed annular chamber between said wheels comprising a pair of annular elements each secured with respect to one of said wheels and having opposed, outer peripheral, enlarged portions formed with radially extending bearing surfaces 1 Jud other bearing surfaces inclined 'withrespect to the axis of the wheels, and a bearing ring havhaving an enlarged annular portion said portions weach being formed with a radially extending surface adapted to oppose the corresponding surface of the other as a thrust bearing and another surface inclined with-respect to the axis of the wheels, and a bearing-ring having inclined converging surfaces to engage said inclined surfaces of said portions. 7 v

CHARLES S..ASH.

REFERENCES CITED The following references are of record in the fileof this patent:

UNITED STATES PATENTS Name Date Frederickson Apr. 29, 1941 Number 

